Flame resistant ABS polycarbonate mouldable materials

ABSTRACT

A thermoplastic, flame-retardant moulding composition having improved mechanical properties is disclosed. The composition contains 40 to 99 parts by weight of a thermoplastic polycarbonate or polyester carbonate, 0.5 to 60 parts by weight of a graft polymer, 0 to 45 parts by weight of a thermoplastic vinyl copolymer, 0.5 to 20 parts by weight of a mixture of at least one mono- and at least one oligo-phosphorus conforming to the general formula                    
     and 0.05 to 5 parts by weight of a fluorinated polyolefine.

The present invention relates to polycarbonate-ABS moulding compositionswhich are made flame-retardant with phosphorus compounds, and whichexhibit an excellent level of mechanical properties, particularly aconsiderably improved ultimate tensile strength and yield stress as wellas an outstanding tensile modulus of elasticity.

EP-A-0 363 608 describes polymer mixtures comprising an aromaticpolycarbonate and a copolymer or graft copolymer containing styrene, aswell as oligomeric phosphates as flame retardant additives. The level ofmechanical properties of these mixtures is often unsatisfactory forcertain purposes of use.

EP-A-0 704 488 describes moulding compositions comprising an aromaticpolycarbonate, copolymers which contain styrene, and graft polymers witha special graft base, in defined quantitative ratios. These mouldingcompositions have a very good notched bar impact strength, and canoptionally be made flame-retardant with phosphorus compounds. Theirlevel of mechanical properties is not always satisfactory for theproduction of mouldings which are subject to intensified elasticloading.

The object of the present invention is therefore to provideflame-retardant polycarbonate-ABS moulding compositions which, inaddition to the requisite high level of flame-retardancy, have anexcellent ultimate tensile strength and an excellent tensile modulus ofelasticity.

It has now been found that PC/ABS moulding compositions, which containphosphorus compounds according to component D (see below) and a graftpolymer comprising a graft base of defined particle size, can beprocessed to form mouldings with a very good level of mechanicalproperties, particularly under intensified elastic loading also.

The present invention therefore relates to a flame-retardantthermoplastic moulding composition containing

A. 40 to 99, preferably 60 to 98.5 parts by weight, of an aromaticpolycarbonate or polyester carbonate

B. 0.5 to 60, preferably 1 to 40, particularly 2 to 25 parts by weight,of a graft polymer of

B.1 5 to 95, preferably 30 to 80% by weight, of one or more vinylmonomers on

B.2 95 to 5, preferably 20 to 70% by weight of one or more graft baseswith a glass transition temperature <0° C., preferably <−20° C., and anaverage particle size (d₅₀ value) of 0.20 to 0.35 μm, preferably 0.25 to0.30 μm

C. 0 to 45, preferably 0 to 30, most preferably 2 to 25 parts by weightof a thermoplastic vinyl (co)polymer

D. 0.5 to 20 parts by weight, preferably 1 to 18 parts by weight, mostpreferably 2 to 15 parts by weight, of at least one mono- and at leastone oligophosphorus compound of general formula (I)

wherein

R¹, R², R³ and R⁴, independently of each other, each denote a C₁ to C₈alkyl which is optionally halogenated in each case, a C₅ to C₆cycloalkyl, C₆ to C₂₀ aryl or C₇ to C₂₀ aralkyl, which are eachoptionally substituted by an alkyl, preferably a C₁-C₄ alkyl and/or by ahalogen, preferably chlorine or bromine,

n denotes 0 or 1, which are independent of each other.

N denotes 0 to 30, and

X denotes a mono- or polynuclear aromatic radical containing 6 to 30 Catoms; and

E. denotes 0.05 to 5 parts by weight, preferably 0.1 to 1 parts byweight, most preferably 0.1 to 0.5 parts by weight, of a fluorinatedpolyolefine,

wherein the sum of all the parts by weight of A+B+C+D+E is 100.

Moulding compositions which are particularly preferred are those inwhich the ratio by weight of components B:C is between 2:1 and 1:4,preferably between 1:1 and 1:3.

In the moulding compositions according to the invention, component D ispreferably present as a mixture of 10 to 90% by weight, preferably 12 to40% by weight, of at least one monophosphorus compound of formula (I),and 10 to 90% by weight, preferably 60 to 88% by weight, with respect tothe total amount of phosphorus compounds in each case, of at least oneoligophosphorus compound of formula (I), wherein the mixture has anaverage N of 0.3 to 20, preferably 0.5 to 10, most preferably 0.5 to 6.

COMPONENT A

Aromatic polycarbonates and/or aromatic polyester carbonates accordingto component A which are suitable according to the invention are knownfrom the literature or can be produced by methods known from theliterature (for example, for the production of aromatic polycarbonates,see Schnell, “Chemistry and Physics of Polycarbonates”, IntersciencePublishers, 1964, as well as DE-AS 1 495 626, DE-OS 2 232 877, DE-OS 2703 376, DE-OS 2 714 544, DE-OS 3 000 610 and DE-OS 3 832 396; for theproduction of aromatic polyester carbonates see DE-OS 3 077 934 forexample).

The production of aromatic polycarbonates is effected, for example, bythe reaction of diphenols with carbonic acid halides, preferablyphosgene, and/or with aromatic dicarboxylic acid dihalides, preferablybenzenedicarboxylic acid dihalides, by the phase boundary method,optionally with the use of chain terminators e.g. monophenols, andoptionally with the use of trifunctional branching agents or branchingagents with a functionality higher than three, for example triphenols ortetraphenols.

Diphenols for the production of the aromatic polycarbonates and/oraromatic polyester carbonates are preferably those of formula (II)

wherein

A denotes a single bond, a C₁-C₅ alkylene, a C₂-C₅ alkylidene, a C₅-C₆cycloalkylidene, —O—, —SO—, —CO—, —S—, —SO₂—, or a C₆-C₁₂ arylene, on towhich other aromatic rings, which optionally contain hetero atoms, canbe condensed,

or a radical of formula (III) or (IV)

B denotes hydrogen a C₁-C₁₂ alkyl, preferably methyl, or a halogen,preferably chlorine and/or bromine, in each case

x is 0.1 or 2, independently of each other, in each case.

p is 1 or 0, and

R⁵ and R⁶, which are independent of each other and are individuallyselectable for each X¹, denote hydrogen or a C₁-C₆ alkyl, preferablyhydrogen, methyl or ethyl.

X¹ denotes carbon, and

m denotes an integer from 4 to 7, preferably 4 or 5, with the provisothat R⁵ and R⁶ simultaneously denote an alkyl on at least one X¹ atom.

The preferred diphenols are hydroquinone, resorcinol,dihydroxydiphenols, bis-(hydroxyphenyl)-C₁-C₅-alkanes,bis-(hydroxyphenyl)-C₅-C₆-cycloalkanes, bis(hydroxyphenyl)-ethers,bis-(hydroxyphenyl)-sulphoxides, bis-(hydroxyphenyl)ketones,bis-(hydroxyphenyl)-sulphones andα,α′-bis-(hydroxyphenyl)-diisopropylbenzenes, as well as derivativesthereof which have brominated and/or chlorinated nuclei.

Diphenols which are particularly preferred are 4,4′-dihydroxydiphenyl,bisphenol A, 2,4-bis(4-hydroxyphenyl)-2-methylbutane,1,1-bis-(4-hydroxyphenyl)-cyclohexane,1,1-bis-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane,4,4,-dihydroxydiphenyl sulphide and 4,4,-dihydroxydiphenyl-sulphone, aswell as di- and tetrabrominated or chlorinated derivatives thereof, suchas 2,2-bis(3-chloro-4-hydroxyphenyl)-propane,2,2-bis-(3,5-dichloro-4-hydroxyphenyl)-propane or2,2-bis-(3,5-dibromo-4-hydroxyphenyl)-propane.

2,2-bis-(4-hydroxyphenyl)-propane (bisphenol A) is particularlypreferred.

The diphenols can be used individually or as arbitrary mixtures.

The diphenols are known from the literature or can be obtained bymethods known from the literature.

Examples of suitable chain terminators for the production of thethermoplastic, aromatic polycarbonates include phenol, p-chlorophenol,p-tert.-butylphenol or 2,4,6-tribromophenol, as well as long chainalkylphenols such as 4-(1,3-tetramethyl-butyl)-phenol according to DE-OS2 842 005 or monoalkylphenols or dialkylphenols which contain a total of8 to 20 C atoms in their alkyl substituents, such as3,5-di-tert.-butyl-phenol, p-iso-octylphenol, p-tert.-octylphenol,p-dodecylphenol, 2-(3,5-dimethylheptyl)-phenol and4-(3,5-dimethylheptyl)-phenol. The amount of chain terminators used isgenerally between 0.5 mole % and 10 mole % with respect to the molar sumof the diphenols used in each case.

The thermoplastic, aromatic polycarbonates have mean weight averagemolecular weights (M_(w), as measured by ultracentrifuging or byscattered light measurements) of 10,000 to 200,000, preferably 20,000 to80,000.

The thermoplastic, aromatic polycarbonates can be branched in the knownmanner, in fact by the incorporation of 0.05 to 2.0 mole %, with respectto the sum of the diphenols used, of trifunctional compounds or ofcompounds with a functionality higher than three, for example thosewhich contain three or more phenolic groups.

Both homopolycarbonates and copolycarbonates are suitable. For theproduction of copolycarbonates according to component A) in accordancewith the invention, 1 to 25% by weight, preferably 2.5 to 25% by weight(with respect to the total amount of diphenols to be used) ofpolydiorganosiloxanes comprising hydroxy-aryloxy terminal groups canalso be used. These are known (see, for example, U.S. Pat. No.3,419,634) or can be produced by methods known from the literature. Forexample, the production of copolycarbonates which containpolydiorganosiloxanes is described in DE-OS 3 334 782.

Apart from bisphenol A homopolycarbonates, the preferred polycarbonatesare the copolycarbonates of bisphenol A with up to 15 mole %, withrespect to the molar sums of the diphenols, of other diphenols which arecited as preferred or particularly preferred, in particular2,2-bis(3,5-dibromo-4-hydroxyphenyl)-propane.

The preferred aromatic dicarboxylic acid dihalides for the production ofthe aromatic polyester carbonates are the diacid dichlorides ofisophthalic acid, terephthalic acid, diphenyl ether-4,4′-dicarboxylicacid and naphthalene-2,6-dicarboxylic acid.

Mixtures of the diacid dichlorides of isophthalic acid and terephthalicin a ratio between 1:20 and 20:1 are particularly preferred.

A carbonic acid halide, preferably phosgene, is used in conjunction as adifunctional acid derivative during the production of the polyestercarbonates.

Apart from the aforementioned monophenols, suitable chain terminatorsfor the production of the aromatic polyester carbonates includechlorocarboxylic acid esters thereof, as well as the acid chlorides ofaromatic monocarboxylic acids which may optionally be substituted byC₁-C₂₂ alkyl groups, or by halogen atoms, and also include aliphaticC₂-C₂₂ monocarboxylic acid chlorides.

The amount of chain terminator is 0.1 to 10 mole % in each case, withrespect to the moles of diphenols in the case of phenolic chainterminators and with respect to the moles of dicarboxylic aciddichlorides in the case of monocarboxylic acid chloride chainterminators.

The aromatic polyester carbonates may also contain incorporatedhydroxycarboxylic acids.

The aromatic polyester carbonates may be either linear or may bebranched in the known manner (see DE-OS 2 940 024 and DE-OS 3 007 934 inthis respect also).

Tri- or multi-functional carboxylic acid chlorides can be used asbranching agents, such as trimesic acid trichloride, cyanuric acidtrichloride, 3,3′-,4,4′-benzophenonetetracarboxylic acid tetrachloride,1,4,5,8-naphthalene-tetracarboxylic acid tetrachloride or pyromelliticacid tetrachloride for example, in amounts of 0.01 to 1.0 mole % (withrespect to the dicarboxylic acid dichlorides used) or tri- ormulti-functional phenols such as phloroglucinol,4,6-dimethyl-2,4,6,-tri-(4-hydroxyphenyl)-heptene-2,4,4-dimethyl-2,4,6-tri-(4-hydroxyphenyl)-heptane,1,3,5-tri-(4-hydroxy-phenyl)-benzene,1,1,1-tri-(4-hydroxy-phenyl)-ethane,tri-(4-hydroxyphenyl)-phenyl-methane,2,2-bis[4,4-bis(4-hydroxyphenyl)-cyclohexyl]-propane,2,4-bis(4-hydroxyphenyl-isopropyl)-phenol,tetra-(4-hydroxyphenyl)-methane,2,6-bis(2-hydroxy-5-methyl-benzyl)4-methyl-phenol,2-(4-hydroxyphenyl)-2-(2,4-dihydroxyphenyl)-propane,tetra-(4-[4-hydroxyphenyl-isopropyl]-phenoxy)-methane or1,4-bis[4,4′-dihydroxytriphenyl)-methyl]benzene, in amounts of 0.01 to1.0 mole % with respect to the diphenols used. Phenolic branching agentscan be placed in the reaction vessel with the diphenols. Acid chloridebranching agents can be introduced together with the acid chlorides.

The proportion of carbonate structural units in the thermoplastic,aromatic polyester carbonates can be arbitrarily varied. The content ofcarbonate groups is preferably up to 100 mole %, particularly up to 80mole %, most preferably up to 50 mole %, with respect to the sum ofester groups and carbonate groups. Both the ester and the carbonatefraction of the aromatic polyester carbonates can be present in the formof blocks, or can be randomly distributed in the condensation polymer.

The relative solution viscosity (η_(rel))of the aromatic polyestercarbonates falls within the range of 1.18 to 1.4, preferably 1.22 to 1.3(as measured on solutions of 0.5 g polyester carbonate in 100 mlmethylene chloride at 25° C.).

The thermoplastic, aromatic polycarbonates and polyester carbonates canbe used on their own or in any mixture with each other.

COMPONENT B

Component B comprises one or more graft copolymers of

B.1 5 to 95, preferably 30 to 80% by weight, of one or more vinylmonomers on

B.2 95 to 5, preferably 70 to 20% by weight of one or more graft baseswith a glass transition temperature<0° C. preferably <−20° C. and anaverage particle size (d₅₀ value) of 0.20 to 0.35 μm.

Monomers B.1 are preferably mixtures of

B1.1 50 to 99 parts by weight of aromatic vinyl compounds and/oraromatic vinyl compounds with substituted nuclei (such as styrene,α-methylstyrene, p-methylstyrene or p-chlorostyrene for example) and/orC₁-C₄ alkyl esters of (meth)acrylic acid (such as methyl methacrylate orethyl methacrylate for example), and

B1.2 1 to 50 parts by weight vinyl cyanides (unsaturated nitriles, suchas acrylonitrile and methacrylonitrile for example) and/or C₁-C₄ alkylesters of (meth)acrylic acid (such as methyl methacrylate, n-butylacrylate and t-butyl acrylate for example) and/or derivatives (such asanhydrides and imides) of unsaturated carboxylic acids (for examplemaleic anhydride and N-phenylmale inimide).

The preferred monomers B.1.1 are selected from at least one of themonomers styrene, α-methylstyrene and methyl methacrylate. The preferredmonomers B.1.2 are selected from at least one of the monomersacrylonitrile, maleic anhydride and methyl methacrylate.

The monomers which are particularly preferred are styrene as B.1.1 andacrylonitrile as B.1.2.

Examples of suitable graft bases B.2 for graft polymers B. include dienerubbers, EP(D)M rubbers, namely those based on ethylene/propylene- andoptionally diene, acrylate, polyurethane, silicone, chloroprene andethylene/vinyl acetate rubbers.

The preferred graft bases B.2 are diene rubbers (e.g. those based onbutadiene, isoprene etc.) or mixtures of diene rubbers or copolymers ofdiene rubbers or mixtures thereof with other copolymerisable monomers(e.g. according to B.1.1 and B.1.2), with the proviso that the glasstransition temperature of component B.2 is less than 0° C.

Pure polybutadiene rubber is particularly preferred.

Examples of particularly preferred polymers B. include ABS polymers(emulsion, bulk and suspension ABS), such as those which are described,for example, in DE-OS 2 035 390 (=US-PS 3 644 574) or in DE-OS 2 248 242(=GB-PS 1 409 275) or in Ullmann. Enzyklopäddie der Technischen Chemie,Volume 19 (1980), page 280 et seq. The gel content of graft base B.2 isat least 30% by weight, preferably at least 40% by weight (as measuredin toluene), and the average particle diameter of graft base B.2 is 0.20to 0.35 μm, preferably 0.25 to 0.30 μm.

Graft copolymers B. are produced by radical polymerisation, e.g. byemulsion, suspension, solution or bulk polymerisation, preferably byemulsion polymerisation.

ABS polymers, which are produced by redox initiation with an initiatorsystem comprising an organic hydroperoxide and ascorbic acid accordingto U.S. Pat. No. 4,937,285, are particularly suitable graft rubbers.

Suitable acrylate rubbers according to B.2 of polymer B are preferablypolymers of acrylic acid alkyl esters, optionally with up to 40% byweight, with respect to B.2, of other polymerisable, ethylenicallyunsaturated monomers. The preferred polymerisable acrylic acid estersinclude C₁-C₈ alkyl esters, for example methyl, ethyl, butyl, n-octyland 2-ethylhexyl esters: halogenoalkyl esters, preferablyhalogeno-C₁-C₈-alkyl esters such as chloroethyl acrylate, as well asmixtures of these monomers.

Monomers with more than one polymerisable double bond can becopolymerised to provide crosslinking. The preferred examples ofcrosslinking monomers are the esters of unsaturated monocarboxylic acidscontaining 3 to 8 C atoms and unsaturated monohydric alcohols containing3 to 12 C atoms, or saturated polyols containing 2 to 4 OH groups and 2to 20 C atoms, such as ethylene glycol dimethacrylate or allylmethacrylatc for example; multiply-unsaturated heterocyclic compounds,such as trivinyl and triallyl cyanurate for example; polyfunctionalvinyl compounds such as di- and trivinylbenzenes; and also triallylphosphate and diallyl phthalate.

The preferred crosslinking monomers are allyl methacrylate, ethyleneglycol dimethacrylate, diallyl phthalate and heterocyclic compoundswhich contain at least 3 ethylenically unsaturated groups.

Crosslinking monomers which are particularly preferred are the cyclicmonomers triallyl cyanurate, triallyl isocyanurate, triacryloylhexahydro-s-triazine and triallylbenzenes. The amount of crosslinkedmonomer is preferably 0.02 to 5, particularly 0.05 to 2% by weight, withrespect to graft base B.2.

For cyclic crosslinking monomers containing at least 3 ethylenicallyunsaturated groups, it is advantageous to restrict the amount thereof toless than 1% by weight of graft base B.2.

Examples of preferred “other” polymerisable, ethylenically unsaturatedmonomers which can optionally be employed apart from acrylic acid estersfor the production of graft base B.2 include acrylonitrile, styrene,α-methylstyrene, acrylamides, vinyl-C₁-C₆-alkyl ethers, methylmethacrylate and butadiene. The acrylate rubbers which are preferred asgraft base B.2 are emulsion polymers which have a gel content of atleast 60% by weight.

Other graft bases which are suitable according to B.2 are siliconerubbers with graft-active sites, such as those described in DE-OS 3 704657, DE-OS 3 704 655, DE-OS 3 631 540 and DE-OS 3 631 539.

The gel content of graft base B.2 is determined at 25° C. in a suitablesolvent (M. Hoffmann. H. Krömer. R. Kuhn, Polymeranalytik I and II,Georg Thieme-Verlag, Stuttgart 1977).

The average particle size d₅₀ is the diameter above and below which 50%of the particles lie in each case. It can be determined by means ofultracentrifuge measurements (W Scholtan, H. Lange, Kolloide, Z. and Z.Polymere 250 (1972), 782-1796).

Since, as is known, the graft monomers are not actually graftedcompletely on to the graft base during the grafting reaction, graftpolymers B. are also to be understood according to the invention toinclude those products which are obtained by (co)polymerisation of thegraft monomers in the presence of the graft base and which occur inconjunction during processing.

COMPONENT C

Component C comprises one or more thermoplastic vinyl (co)polymers.

Polymers which are suitable as component C. are polymers of at least onemonomer from the group comprising aromatic vinyl compounds, vinylcyanides (unsaturated nitrites), (meth)acrylic acid (C₁-C₈)-alkylesters, unsaturated carboxylic acids, as well as derivatives (such asanhydrides and imides) of unsaturated carboxylic acids. (Co)polymerswhich are particularly suitable are those of

C.1 50 to 99, preferably 60 to 80 parts by weight of aromatic vinylcompounds and/or aromatic vinyl compounds which comprise substitutednuclei, such as styrene, α-methylstyrene, p-methylstyrene,p-chlorostyrene) and/or methacrylic acid (C₁-C₄)-alkyl esters, such asmethyl methacrylate or ethyl methacrylate for example), and

C.2 1 to 50, preferably 20 to 40 parts by weight vinyl cyanides(unsaturated nitrites) such as acrylonitrile and methacrylonitrileand/or (meth)acrylic acid (C₁-C₈) esters (such as methyl methacrylate,n-butyl acrylate or t-butyl acry late for example) and/or unsaturatedcarboxylic acids (such as maleic acid) and/or derivatives (such asanhydrides and imides) of unsaturated carboxylic acids (for examplemaleic anhydride and N-phenyl-maleinimide).

(Co)polymers C are resin-like, thermoplastic and free from rubber.

The copolymer of C.1 styrene and C.2 acrylonitrile is particularlypreferred.

The (co)polymers according to C are known, and can be produced byradical polymerisation, particularly by emulsion, suspension, solutionor bulk polymerisation. The (co)polymers according to component Cpreferably have molecular weights M_(w) (weight average, determined bylight scattering or sedimentation) between 15,000 and 200,000.

(Co)polymers according to component C are frequently produced asby-products during the graft polymerisation of component B, particularlywhen large amounts of monomers B.1 are grafted on to small amounts ofrubber B.2. The amount of C which can also optionally be used accordingto the invention does not include these by-products of the graftpolymerisation of B.

However, component C should be present in the moulding compositionsaccording to the invention for certain purposes of use.

If component C is present in the moulding compositions, the ratio byweight of components B:C should be between 2:1 and 1:4, preferablybetween 1:1 and 1:2, in order to obtain the desired level of mechanicalproperties for certain purposes of use.

COMPONENT D

Component D is a mixture of at least one mono- and of at least oneoligomeric phosphorus compound of formula (I).

In this formula, R¹, R², R³ and R⁴ have the meanings given above, R¹,R², R³ and R⁴ preferably denote, independently of each other, C₁-C₄alkyl, phenyl, naphthyl or phenyl-C₁-C₄-alkyl. The aromatic groups R¹,R², R³ and R⁴ may themselves be substituted with halogen and/or alkylgroups, preferably chlorine, bromine and/or C₁-C₄-alkyl. The mostpreferred aryl radicals are cresyl, phenyl, xylenyl, propylphenyl orbutylphenyl, as well as the corresponding brominated and chlorinatedderivatives thereof.

X in formula (I) denotes a mono- or polynuclear aromatic radicalcontaining 6 to 30 C atoms. This is derived from diphenols, such asdiphenyl-phenol, bisphenol A, resorcinol or hydroquinone for example, orfrom chlorinated or brominated derivatives thereof.

n in formula (I) can be 0 or 1, independently of each other, n ispreferably equal to 1.

N represents values of 0 to 30, and preferably represents an averagevalue of 0.3 to 20, most preferably 0.5 to 10, particularly 0.5 to 6.

Mixtures are used as component D according to the invention whichpreferably comprise 10 to 90% by weight, most preferably 12 to 40% byweight, of at least one monophosphorus compound of formula (I) and of atleast one oligomeric phosphorus compound, or which comprise a mixture ofoligomeric phosphorus compounds in amounts of 10 to 90% by weight,preferably 60 to 88% by weight, with respect to the total amount ofphosphorus compounds.

Particular monophosphorus compounds of formula (I) are tributylphosphate, tris-(2-chloroethyl)-phosphate, tris-(2,3-dibromopropyl)phosphate, triphenyl phosphate, tricresyl phosphate, diphenyl cresylphosphate, diphenyl octyl phosphate, diphenyl-2-ethyl-cresyl phosphate,tri-(isopropylphenyl) phosphate, halogen-substituted aryl phosphates,methylphosphonic acid dimethyl ester, methylphosphonic acid diphenylester, phenylphosphonic acid diethyl ester, triphenylphosphine oxide ortricresylphosphine oxide.

The mixtures of monomeric and oligomeric phosphorus compounds of formula(I) have average N values of 0.3 to 20, preferably 0.5 to 10,particularly 0.5 to 6.

The phosphorus compounds according to component D are known (see, forexample, EP-A 363 608, EP-A 640 655) or can be prepared in an analogousmanner by known methods (e.g. Ullmanns Encyklopädie der technischenChemie, Volume 8, page 301 et seq. 1979; Houben-Weyl, Methoden derorganischen Chemie, Volume 12/1 page 43; Beilstein Volume 6, page 177).

COMPONENT E

Fluorinated polyolefines E) are of high molecular weight and have glasstransition temperatures above −30° C. generally above 100° C. Theypreferably have fluorine contents of 65 to 76, particularly 70 to 76% byweight, and average particle diameters d₅₀ of 0.05 to 1000, preferably0.08 to 20 μm. In general, fluorinated polyolefines E) have a density of1.2 to 2.3 g/cm³. The preferred fluorinated polyolefines E) arepolytetrafluoroethylene, polyvinylidene fluoride, andtetrafluoroethylene (hexafluoropropylene) andethylene/tetrafluoroethylene copolymers. These fluorinated polyolefinesare known (see “Vinyl and Related Polymers” by Schildknecht, John Wiley& Sons, Inc., New York, 1962, pages 484-494; “Fluoropolymers” by Wall,Wiley-Interscience, John Wiley & Sons, Inc., New York, Volume 13, 1970,pages 623-654; “Modern Plastics Encyclopedia”, 1970-1971, Volume 47,No.10 A, October 1970. McGraw-Hill, Inc., New York, pages 134 and 774;“Modern Plastics Encyclopedia”, 1975-1976. October 1975, Volume 52,No.10 A, McGraw-Hill, Inc., New York, pages 27, 28 and 472; and U.S.Pat. Nos. 3,671,487, 3,723,373 and 3,838,092).

They can be produced by known methods, for example by the polymerisationof tetrafluoroethylene in aqueous medium with a catalyst which formsfree radicals, for example sodium, potassium or ammoniumperoxydisulphate, at pressures of 7 to 71 kg/cm² and at temperatures of0 to 200° C., preferably at temperatures of 20 to 100° C. (for furtherdetails, for example, see U.S. Pat. No. 2,393,967). Depending on theform in which they are used, the density of these materials may bebetween 1.2 and 2.3 g/cm³, and their average particle size may bebetween 0.5 and 1000 μm.

The polyolefines E) which are preferred according to the invention aretetrafluoroethylene polymers with average particle diameters of 0.05 to20 μm, preferably 0.08 to 10 μm, and a density of 1.2 to 1.9 g/cm³. Theyare preferably used in the form of a coagulated mixture of emulsions oftetrafluoroethylene polymers E) with emulsions of graft polymers B).

Tetrafluoroethylene polymers with average particle diameters of 100 to1000 μm and densities of 2.0 g/cm³ to 2.3 g/cm³ are suitable fluorinatedpolyolefines E) which can be used in powder form.

To prepare a coagulated mixture of B) and E), an aqueous emulsion(latex) of a graft polymer B) is first mixed with a finely dispersedemulsion of a tetraethylene polymer E); suitable tetrafluoroethylenepolymer emulsions usually have solids contents of 30 to 70% by weight,particularly 50 to 60% by weight, preferably 30 to 35% by weight.

The quantitative data in the description of component B may include theproportion of graft polymer for the coagulated mixture of graft polymerand fluorinated polyolefines.

In the emulsion mixture, the equilibrium ratio of graft polymer B totetrafluoroethylene polymer E is 95:5 to 60:40. The emulsion mixture issubsequently coagulated in the known manner, for example byspray-drying, freeze-drying, or by coagulation by means of addinginorganic or organic salts, acids or bases, or organic solvents whichare miscible with water, such as alcohols or ketones, preferably attemperatures of 20 to 150° C. particularly 50 to 100° C. If necessary,it can be dried at 50 to 200° C., preferably 70 to 100° C.

Suitable tetrafluoroethylene polymer emulsions are commerciallyavailable products, and are sold by the DuPont company as Teflon® 30 N.

The moulding compositions according to the invention may contain atleast one of the customary additives, such as internal lubricants anddemoulding agents, nucleating agents, anti-static agents andstabilisers, as well as colorants and pigments.

In addition, the moulding compositions according to the invention mayalso contain very finely divided inorganic powders in an amount of up to50 parts by weight, preferably up to 20 parts by weight and particularlyfrom 0.5 to 10 parts by weight.

These very finely divided inorganic compounds consist of one or moremetals from main groups 1 to 5 or from subgroups 1 to 8 of the periodictable of the elements, preferably from main groups 2 to 5 and fromsubgroups 4 to 8, most preferably from main groups 3 to 5 and subgroups4 to 8, in combination with at least one element selected from the groupcomprising oxygen, sulphur, boron, phosphorus, carbon, nitrogen,hydrogen and silicon.

Examples of preferred compounds include oxides, hydroxides, hydratedoxides, sulphates, sulphites, sulphides, carbonates, carbides, nitrates,nitrites, nitrides, borates, silicates, phosphates, hydrides, phosphitesor phosphonates.

Particular examples of preferred, very finely divided inorganiccompounds include TiN, TiO₂, SnO₂, WC, ZnO, Al₂O₃, AlO(OH), ZrO₂, Sb₂O₃,SiO₂, iron oxides, Na₂SO₄, BaSO₄, vanadium oxides, zinc borate,silicates such as Al silicates, Mg silicates, and one-two- orthree-dimensional silicates. Mixtures and doped compounds can also beused. Moreover, the surfaces of these nano-scale particles can bemodified with organic molecules in order to improve the compatibilitythereof with polymers. Hydrophobic or hydrophilic surfaces can beproduced in this manner.

The average particle diameters are less than or equal to 200 nm,preferably less than or equal to 150 nm, particularly 1 to 100 nm.

The expressions “particle size” and “particle diameter” always denotethe average particle diameter d₅₀ as determined by ultracentrifugemeasurements as described by W. Scholtan et al., Kolloid-Z. und Z.Polymere 250 (1972), pages 782 to 796.

The inorganic compounds may exist as powders, pastes, sols, dispersionsor suspensions. Powders can be obtained by precipitation fromdispersions, sols or suspensions.

The powders can be incorporated in the synthetic thermoplastic materialsby customary methods, for example by the direct kneading or extrusion ofthe constituents of the moulding composition and the very finely dividedinorganic powders. The preferred methods are the preparation of a masterbatch, e.g. comprising flame retardant additives, other additives,monomers and solvents in component A, or co-precipitation fromdispersions of the graft rubbers together with dispersions, suspensions,pastes or sols of the very finely divided inorganic materials.

The moulding compositions according to the invention may contain up to35% by weight, with respect to the total moulding composition, of afurther flame retardant which optionally has a synergistic effect.Examples of further flame retardants include organic halogen compoundssuch as decabromobisphenyl ether, tetrabromobisphenol, inorganic halogencompounds such as ammonium bromide, nitrogen compounds such as melamine,melamine-formaldehyde resins, inorganic hydroxide compounds such as Mgor Al hydroxide, inorganic compounds such as antimony oxide, bariummetaborate, hydroxoantimonate, zirconium oxide, zirconium hydroxide,molybdenum oxide, ammonium molybdate, zinc borate, ammonium borate,barium metaborate and tin oxide, as well as siloxane compounds.

The moulding compositions according to the invention, which containcomponents A) to E) and optionally other known additives such asstabilisers, colorants, pigments, internal lubricants, demoulding agentsand nucleating agents, as well as anti-static agents, are produced bymixing the respective constituents in the known manner, and bycompounding and extruding them in the melt, at temperatures of 200° C.to 300° C., in customary processing units such as internal kneaders,extruders and twin-shaft endless screw devices, wherein component E) ispreferably used in the form of the aforementioned coagulated mixture.

Mixing of the individual constituents can be effected eithersuccessively or simultaneously, in the known manner, and either at about20° C. (room temperature) or at elevated temperature.

Due to their excellent flame-resistance, their very good processingproperties and their very good mechanical properties, particularly theiroutstanding rigidity, the thermoplastic moulding compositions accordingto the invention are suitable for the production of mouldings of anytype, particularly those which are subject to the requirement ofincreased fracture-resistance.

The moulding compositions of the present invention can be used for theproduction of mouldings of any type. Mouldings can be produced byinjection moulding in particular. Examples of mouldings which can beproduced include housing parts of any type, e.g. for domestic appliancessuch as juice presses, coffee machines or mixers, or for officemachines, covering panels for the building sector and parts for themotor vehicle sector. These mouldings can also be used in the field ofelectrical engineering, because they have very good electricalproperties.

Another form of processing is the production of mouldings by the swagingof previously produced panels or sheets.

Therefore, the present invention further relates to the use of themoulding compositions according to the invention for the production ofmouldings of any type, preferably of the type mentioned above, and alsorelates to mouldings from the moulding compositions according to theinvention.

EXAMPLES Component A

A linear polycarbonate based on bisphenol A, with a relative solutionviscosity of 1.252, as measured in CH₂Cl₂ as the solvent at 25° C. andat a concentration of 0.5 g/100 ml.

Component B

A graft polymer of 45 parts by weight of a copolymer of styrene andacrylonitrile in a ratio of 72:28 on 55 parts by weight of particulate,crosslinked polybutadiene rubber (average particle diameter d₅₀ 0.28μm), produced by emulsion polymerisation.

Component C

A styrene/acrylonitrile copolymer with a ratio by weight ofstyrene/acrylonitrile of 72.28 and a limiting viscosity 0.55 dl/g (asmeasured in dimethylformamide at 20° C.).

Component D.1

A mixture of m-phenylene-bis(di-phenyl-phosphate) (Fyrolflex RDPsupplied by Akzo) and triphenyl phosphate (TPP) in a ratio by weight of3:1.

Component D.2

Triphenyl phosphate (TPP) as a comparison.

Component E

A tetrafluoroethylene polymer as a coagulated mixture of an SAN graftpolymer emulsion according to the aforementioned component B in waterand a tetrafluoroethylene polymer emulsion in water. The ratio by weightof graft polymer B to tetrafluoroethylene polymer E in the mixture was90% by weight to 10% by weight. The tetrafluoroethylene polymer emulsionhad a solids content of 60% by weight, and its average particle diameterwas between 0.05 and 0.5 μm. The SAN graft polymer emulsion had a solidscontent of 34% by weight and an average latex particle diameter ofd₅₀=0.28 μm.

Production of E

The emulsion of the tetrafluoroethylene polymer (Teflon 30 N supplied byDuPont) was mixed with the emulsion of SAN graft polymer B and wasstabilised with 1.8% by weight, with respect to the polymer solids, ofphenolic anti-oxidants. The mixture was coagulated at 85 to 95° C. withan aqueous solution of MgSO₄ (Epsom salts) and acetic acid at pH 4 to 5,was filtered and washed until practically free from electrolyte, wassubsequently freed from the bulk of the water by centrifuging, andthereafter was dried at 100°0 C. to form a powder. This powder couldthen be compounded with the other components in the processing unitsdescribed above.

Production and Testing of Moulding Compositions According to theInvention

The components were mixed in a 3-liter internal kneader. Mouldings wereproduced in an Arburg Type 270 E injection moulding machine at 260° C.

The Vicat B thermal deformation resistance was determined according toDIN 53 460 (ISO 306) on bars of dimensions 80×10×4 mm³.

The tensile modulus of elasticity was determined according to DIN 53457/ISO 527.

The yield stress was determined according to ISO 527.

The ultimate tensile strength (tensile test) was determined according toISO 527/DIN 53455.

TABLE 1 Composition and properties of polycarbonate- ABS mouldingcompositions Example 1 (comparative) 2 Components [parts by weight] A83.8 83.8 B 4.3 4.3 C 2.7 2.7 D.1 — 6.8 D.2 6.8 — E 2.4 2.4 Properties:Vicat B [° C.] 107 110 Ultimate tensile strength 47.2 49.7 [N/mm²] Yieldstress 58.0 61.1 [N/mm²] Tensile modulus of elasticity 2628 2651 [N/mm²]

What is claimed is:
 1. Thermoplastic, flame-retardent mouldingcompositions, containing A. 40 to 99 parts by weight of a thermoplasticpolycarbonate of polyester carbonate, B. 0.5 to 60 parts by weight of agraft polymer of B.1 5 to 95% by weight of one or more vinyl monomers onB.2 95 to 5 by weight of one or more graft bases with glass transitiontemperature <0° C. and average particle size (d₅₀ value) of 0.20 to 0.35μm. C. 0 to 45 parts by weight of a thermoplastic vinyl copolymer D. 0.5to 20 parts by weight of a mixture of at least one mono- and at leastone oligo-phosphorus compound of general formula (I)

wherein R¹, R², R³ and R⁴, independently of each other, each denote a C₁to C₈ alkyl which is optionally halogenated, a C₅ to C₆ cycloalkyl, C₆to C₂₀ aryl or C₇ to C₂₀ aralkyl, which are each optionally substitutedby an alkyl, and/or by a halogen, n denotes 0 or 1, which areindependent of each other, N denotes 0 to 30, and X denotes a mono- orpolynuclear aromatic radical containing 6 to 30 C atoms, and E denotes0.05 to 5 parts by weight of a fluorinated polyolefine.
 2. Mouldingcompositions according to claim 1 which contain 40 parts by weight ofcomponent B and 0 to 30 parts by weight of component C.
 3. Mouldingcompositions according to claim 1, wherein the average particle size d₅₀of component B is 0.25 to 0.30 μm.
 4. Moulding compositions according toclaim 1, wherein the ratio by weight of components B:C is between 2:1and 1:4.
 5. Moulding compositions according to claim 1 which contain 10to 90% by weight of at least one monophosphate compound of formula (I)and 90 to 10% by weight (with respect to the total amount of phosphoruscompounds in each case) of at least one oligophosphorus compound offormula (I).
 6. Moulding compositions according to claim 1, wherein N informula (I) has an average value of 0.3 to 2.0.
 7. Moulding compositionsaccording to claim 1 which contain tip to 35% by weight, with respect tothe total moulding composition, of at least one flame retardant which isdifferent from component D.
 8. Moulding compositions according to claim1, which contain 1 to 18 parts by weight of component D.
 9. Mouldingcompositions according to claim 1, wherein graft base B.2 is a dienerubber, an acrylate rubber, a silicone rubber or an ethylene-propylenediene rubber.
 10. Mouldings produced from moulding compositionsaccording to claim
 1. 11. The molding composition according to claim 1wherein monophosphorus compound of formula (I) is at least one memberselected from the group consisting of tributyl phosphate,tris-(2-chloroethyl) phosphate, tris-(2,3-dibromopropyl) phosphate,triphenyl phosphate, tricresyl phosphate, diphenyl cresyl phosphate,diphenyl octyl phosphate, diphenyl-2-ethyl-cresyl phosphate,tri-(isopropylphenyl) phosphate, halogen-substituted aryl phosphates,methylphosphonic acid dimethyl ester, methylphosphonic acid diphenylester, phenylphosphonic acid diethyl ester, triphenylphosphine oxide andtricresylphosphine oxide.
 12. The molding composition according to claim1 further containing a very finely divided compound having averageparticle diameter of less than or equal to 200 nm comprising an elementfrom main groups 1 to 5 or from subgroups 1 to 8 of the periodic tableof the elements, in combination with at least one element selected fromthe group consisting of oxygen, sulphur, boron, carbon, phosphorus,nitrogen, hydrogen and silicon.
 13. The molding composition according toclaim 1 which further contains at least one additive selected from thegroup consisting of stabilizers, pigments, demoulding agents, flowenhancers and anti-static agents.
 14. The molding composition of claim 1wherein said C is present in an amount of 2 to 25 part by weight.